Drawing interface for 2D graphics. More...

#include <painter.h>

Classes
struct	AutoGroup
	You are encouraged to use this instead of manually calling Painter::push_group() and Painter::pop_group(). More...

struct	AutoSaveRestore
	Scoped save() and restore() for a Painter. More...

Public Types
enum class	AntiAlias { system , none , gray , subpixel , fast , good , best }
	Supported types of anti-aliasing. More...

enum class	LineCap { butt , round , square }
	Supported line caps. More...

using	SubordinateFilter = std::function< bool(const Widget &)>
	Return true if the subordinate widget is filtered out, hence should not be drawn by the painter.

enum class	TextDrawFlag : uint32_t { shadow = detail::bit(0) }

using	TextDrawFlags = Flags< TextDrawFlag >

Public Member Functions
	Painter ()=delete

	Painter (Surface &surface) noexcept

	~Painter ()

EGT_NODISCARD bool	alpha_blending () const
	Get the alpha blending state, either enabled or disabled.

Painter &	alpha_blending (bool enabled)
	Set the alpha blending state either enabled or disabled.

EGT_NODISCARD Painter::AntiAlias	antialias () const
	Get the current type of anti-aliasing.

Painter &	antialias (Painter::AntiAlias value)
	Set the type of anti-aliasing.

Painter &	arc (const ArcF &arc)

Painter &	clip ()

Color	color_at (const Point &point) noexcept

void	color_at (const Point &point, const Color &color) noexcept

EGT_NODISCARD const detail::InternalContext &	context () const
	Get the current underlying context the painter is using.

template<class T >
Painter &	draw (const ArcType< T > &arc)
	Create an arc.

Painter &	draw (const Color &color, const RectF &rect={}, bool preserve=false)

Painter &	draw (const Image &image)
	Draw an image surface at the specified point.

Painter &	draw (const Image &image, const PointF &point, const RectF &rect={})

template<class T >
Painter &	draw (const LineType< T > &line)
	Create a line.

Painter &	draw (const Pattern &pattern, const RectF &rect={}, bool preserve=false)

template<class T >
Painter &	draw (const PointType< T, detail::Compatible::normal > &point)
	Move to a point.

template<class T >
Painter &	draw (const RectType< T > &rect)
	Create a rectangle.

Painter &	draw (const std::string &str, const TextDrawFlags &flags={})
	Draw text inside the specified rectangle.

Painter &	draw (const Surface &surface, const PointF &point, const RectF &rect={})

template<class T >
Painter &	draw (const T &start, const T &end)
	Create a line from the start point to the end point.

EGT_NODISCARD Font::FontExtents	extents () const
	Get the font extents based on the current context, hence taking into account transformations such as rotation or symmetry.

EGT_NODISCARD Font::TextExtents	extents (const std::string &text) const
	Get the text extents based on the current context, hence taking into account transformations such as rotation or symmetry.

Painter &	fill ()

Painter &	fill_preserve ()

EGT_NODISCARD bool	filter_subordinate (const Widget &subordinate) const
	Apply the current subordinate filter.

Painter &	flood (const Point &point, const Color &color)

void	high_fidelity ()
	Configure high fidelity options.

template<class T >
Painter &	line (const PointType< T, detail::Compatible::normal > &point)

EGT_NODISCARD Painter::LineCap	line_cap () const
	Get the current line cap.

Painter &	line_cap (Painter::LineCap value)
	Set the current line cap.

Painter &	line_to (const PointF &point)

Painter &	line_width (float width)
	Set the current line width.

void	low_fidelity ()
	Configure low fidelity options.

Painter &	mask (const Image &image, const Point &point={})

Painter &	mask (const Surface &surface, const PointF &point={})
	Draw an image as a mask.

Painter &	move_to (const PointF &point)

Painter &	paint ()

Painter &	paint (float alpha)

void	pop_group ()
	Pop a group off the stack and automatically make it the source.

void	push_group ()
	Push a group onto the stack.

Painter &	rectangle (const RectF &rect)

void	restore ()
	Restore the previous saved state of the current context.

void	restore_subordinate_filter (SubordinateFilter &&subordinate_filter)
	Restore the subordinate filter from a previous value.

Painter &	rotate (float angle)

void	save ()
	Save the state of the current context.

Painter &	scale (float sx, float sy)

Painter &	set (const Font &font)
	Set the active font.

Painter &	set (const Pattern &pattern)
	Set the current color.

Painter &	set_dash (const double *dashes, size_t num_dashes, double offset)
	Set the dash pattern to be used by stroke().

SubordinateFilter	set_subordinate_filter (const SubordinateFilter &subordinate_filter)
	Set the subordinate filter (nullptr to remove the current filter).

Painter &	show_text (const char *utf8)

Painter &	show_text (const std::string &str)

Painter &	source (const Color &color)
	Set the source pattern from a Color.

Painter &	source (const Image &image, const PointF &point={})
	Set the source pattern from an Image.

Painter &	source (const Pattern &pattern)
	Set the source pattern from a Pattern.

Painter &	source (const Surface &surface, const PointF &point={})
	Set the source pattern from a Surface.

Painter &	stroke ()

void	sync_for_cpu (bool skip_source=false) const
	Claim the painter for being used by the CPU.

EGT_NODISCARD Surface &	target ()

EGT_NODISCARD const Surface &	target () const
	Get the target surface the painter is using.

Size	text_size (const std::string &text)

Painter &	translate (const Point &point)

Painter &	translate (const PointF &point)

Protected Attributes
std::unique_ptr< detail::InternalContext >	m_cr
	Internal context.

SubordinateFilter	m_subordinate_filter
	Internal state.

Surface &	m_surface

Detailed Description

Drawing interface for 2D graphics.

This is the interface for 2D drawing primitives that makes working with and drawing EGT primitives easier.

Member Typedef Documentation

◆ SubordinateFilter

using SubordinateFilter = std::function<bool(const Widget&)>

Return true if the subordinate widget is filtered out, hence should not be drawn by the painter.

◆ TextDrawFlags

using TextDrawFlags = Flags<TextDrawFlag>

Member Enumeration Documentation

◆ AntiAlias

enum class AntiAlias

strong

Supported types of anti-aliasing.

Enumerator
system
none
gray
subpixel
fast
good
best

◆ LineCap

enum class LineCap

strong

Supported line caps.

Enumerator
butt
round
square

◆ TextDrawFlag

enum class TextDrawFlag : uint32_t

strong

Enumerator
shadow

Constructor & Destructor Documentation

◆ Painter() [1/2]

Painter ( )

delete

◆ Painter() [2/2]

Painter ( Surface & surface )

explicitnoexcept

◆ ~Painter()

~Painter ( )

Member Function Documentation

◆ alpha_blending() [1/2]

EGT_NODISCARD bool alpha_blending ( ) const

Get the alpha blending state, either enabled or disabled.

◆ alpha_blending() [2/2]

Painter & alpha_blending ( bool enabled )

Set the alpha blending state either enabled or disabled.

Parameters

[in] enabled Whether the alpha blending is to be enabled.

Note: disabling the alpha blending is like forcing the destination alpha to zero.

◆ antialias() [1/2]

EGT_NODISCARD Painter::AntiAlias antialias ( ) const

Get the current type of anti-aliasing.

◆ antialias() [2/2]

Painter & antialias ( Painter::AntiAlias value )

Set the type of anti-aliasing.

Parameters

[in] value Anti-aliasing type.

◆ arc()

Painter & arc ( const ArcF & arc )

◆ clip()

Painter & clip ( )

◆ color_at() [1/2]

Color color_at ( const Point & point )

noexcept

◆ color_at() [2/2]

void color_at	(	const Point &	point,
		const Color &	color
	)

noexcept

◆ context()

EGT_NODISCARD const detail::InternalContext & context ( ) const

inline

Get the current underlying context the painter is using.

◆ draw() [1/11]

template<class T >

Painter & draw ( const ArcType< T > & arc )

inline

Create an arc.

Parameters

[in] arc The arc.

◆ draw() [2/11]

Painter & draw	(	const Color &	color,
		const RectF &	rect = `{}`,
		bool	preserve = `false`
	)

Parameters

[in]	color	The source color to fill the @rect rectangle with.
[in]	rect	The rectangle to draw, if any, the whole clip region otherwise.
[in]	preserve	If true and @rect is not empty, reset the path to @rect.

◆ draw() [3/11]

Painter & draw ( const Image & image )

Draw an image surface at the specified point.

◆ draw() [4/11]

Painter & draw	(	const Image &	image,
		const PointF &	point,
		const RectF &	rect = `{}`
	)

Parameters

[in]	image	The image source to draw.
[in]	point	The position of the surface origin.
[in]	rect	The rectangle to draw, if any, the whole image otherwise.

◆ draw() [5/11]

template<class T >

Painter & draw ( const LineType< T > & line )

inline

Create a line.

Parameters

[in] line The line.

◆ draw() [6/11]

Painter & draw	(	const Pattern &	pattern,
		const RectF &	rect = `{}`,
		bool	preserve = `false`
	)

Parameters

	[i]	pattern The source pattern to fill the @rect rectangle with.
[in]	rect	The rectangle to draw, if any, the whole clip region otherwise.
[in]	preserve	If true and @rect is not empty, reset the path to @rect.

◆ draw() [7/11]

template<class T >

Painter & draw ( const PointType< T, detail::Compatible::normal > & point )

inline

Move to a point.

Parameters

[in] point The point.

◆ draw() [8/11]

template<class T >

Painter & draw ( const RectType< T > & rect )

inline

Create a rectangle.

Parameters

[in] rect The rectangle.

◆ draw() [9/11]

Painter & draw	(	const std::string &	str,
		const TextDrawFlags &	flags = `{}`
	)

Draw text inside the specified rectangle.

◆ draw() [10/11]

Painter & draw	(	const Surface &	surface,
		const PointF &	point,
		const RectF &	rect = `{}`
	)

Parameters

[in]	surface	The surface source to draw.
[in]	point	The position of the surface origin.
[in]	rect	The rectangle to draw, if any, the whole surface otherwise.

◆ draw() [11/11]

template<class T >

Painter & draw	(	const T &	start,
		const T &	end
	)

inline

Create a line from the start point to the end point.

Parameters

[in]	start	The point.
[in]	end	The point.

◆ extents() [1/2]

EGT_NODISCARD Font::FontExtents extents ( ) const

Get the font extents based on the current context, hence taking into account transformations such as rotation or symmetry.

◆ extents() [2/2]

EGT_NODISCARD Font::TextExtents extents ( const std::string & text ) const

Get the text extents based on the current context, hence taking into account transformations such as rotation or symmetry.

Parameters

[in] text The UTF8 encoded text.

◆ fill()

Painter & fill ( )

◆ fill_preserve()

Painter & fill_preserve ( )

◆ filter_subordinate()

EGT_NODISCARD bool filter_subordinate ( const Widget & subordinate ) const

Apply the current subordinate filter.

Parameters

[in] subordinate The widget to be tested.

Returns: true if the subordinate widget is filtered out, hence should not be drawn by the painter.

◆ flood()

Painter & flood	(	const Point &	point,
		const Color &	color
	)

◆ high_fidelity()

void high_fidelity ( )

Configure high fidelity options.

This configures settings related to font hinting, font aliasing, and shape aliasing.

◆ line()

template<class T >

Painter & line ( const PointType< T, detail::Compatible::normal > & point )

inline

◆ line_cap() [1/2]

EGT_NODISCARD Painter::LineCap line_cap ( ) const

Get the current line cap.

◆ line_cap() [2/2]

Painter & line_cap ( Painter::LineCap value )

Set the current line cap.

Parameters

[in] value Line cap.

◆ line_to()

Painter & line_to ( const PointF & point )

◆ line_width()

Painter & line_width ( float width )

Set the current line width.

Parameters

[in] width Line width.

◆ low_fidelity()

void low_fidelity ( )

Configure low fidelity options.

This configures settings related to font hinting, font aliasing, and shape aliasing.

◆ mask() [1/2]

Painter & mask	(	const Image &	image,
		const Point &	point = `{}`
	)

◆ mask() [2/2]

Painter & mask	(	const Surface &	surface,
		const PointF &	point = `{}`
	)

Draw an image as a mask.

◆ move_to()

Painter & move_to ( const PointF & point )

◆ paint() [1/2]

Painter & paint ( )

◆ paint() [2/2]

Painter & paint ( float alpha )

◆ pop_group()

void pop_group ( )

Pop a group off the stack and automatically make it the source.

See also: AutoGroup

◆ push_group()

void push_group ( )

Push a group onto the stack.

See also: AutoGroup

◆ rectangle()

Painter & rectangle ( const RectF & rect )

◆ restore()

void restore ( )

Restore the previous saved state of the current context.

See also: AutoSaveRestore

◆ restore_subordinate_filter()

void restore_subordinate_filter ( SubordinateFilter && subordinate_filter )

Restore the subordinate filter from a previous value.

Parameters

[in] subordinate_filter The saved subordinate filter to restore.

◆ rotate()

Painter & rotate ( float angle )

◆ save()

void save ( )

Save the state of the current context.

See also: AutoSaveRestore

◆ scale()

Painter & scale	(	float	sx,
		float	sy
	)

◆ set() [1/2]

Painter & set ( const Font & font )

Set the active font.

◆ set() [2/2]

Painter & set ( const Pattern & pattern )

Set the current color.

◆ set_dash()

Painter & set_dash	(	const double *	dashes,
		size_t	num_dashes,
		double	offset
	)

Set the dash pattern to be used by stroke().

Parameters

[in]	dashes	An array specifying alternate lengths of on and off stroke portions.
[in]	num_dashes	The length of the dashes array.
[in]	offset	An offset into the dash pattern at which the stroke should start.

◆ set_subordinate_filter()

SubordinateFilter set_subordinate_filter ( const SubordinateFilter & subordinate_filter )

Set the subordinate filter (nullptr to remove the current filter).

Parameters

[in] subordinate_filter The new subordinate filter.

Returns: a copy of the previous subordinate filter.

◆ show_text() [1/2]

Painter & show_text ( const char * utf8 )

◆ show_text() [2/2]

Painter & show_text ( const std::string & str )

inline

◆ source() [1/4]

Painter & source ( const Color & color )

Set the source pattern from a Color.

◆ source() [2/4]

Painter & source	(	const Image &	image,
		const PointF &	point = `{}`
	)

Set the source pattern from an Image.

◆ source() [3/4]

Painter & source ( const Pattern & pattern )

Set the source pattern from a Pattern.

◆ source() [4/4]

Painter & source	(	const Surface &	surface,
		const PointF &	point = `{}`
	)

Set the source pattern from a Surface.

◆ stroke()

Painter & stroke ( )

◆ sync_for_cpu()

void sync_for_cpu ( bool skip_source = false ) const

Claim the painter for being used by the CPU.

Parameters

[in] skip_source The boolean telling whether the source surface should be ignored.

Wait for all GPU operations, if any, to complete. Synchronize the target surface of the Painter instance. Also synchronize the source surface, if any, unless @skip_source is 'true'. Indeed, the source should be skipped if the rendering operations to come won't use it because a new source is about to be set.

◆ target() [1/2]

EGT_NODISCARD Surface & target ( )

inline

◆ target() [2/2]

EGT_NODISCARD const Surface & target ( ) const

inline

Get the target surface the painter is using.

◆ text_size()

Size text_size ( const std::string & text )

◆ translate() [1/2]

Painter & translate ( const Point & point )

◆ translate() [2/2]

Painter & translate ( const PointF & point )

Member Data Documentation

◆ m_cr

std::unique_ptr<detail::InternalContext> m_cr

protected

Internal context.

◆ m_subordinate_filter

SubordinateFilter m_subordinate_filter

protected

Internal state.

◆ m_surface

Surface& m_surface

protected

Classes

Public Types

Public Member Functions

Protected Attributes

Detailed Description

Member Typedef Documentation

◆ SubordinateFilter

◆ TextDrawFlags

Member Enumeration Documentation

◆ AntiAlias

◆ LineCap

◆ TextDrawFlag

Constructor & Destructor Documentation

◆ Painter() [1/2]

◆ Painter() [2/2]

◆ ~Painter()

Member Function Documentation

◆ alpha_blending() [1/2]

◆ alpha_blending() [2/2]

◆ antialias() [1/2]

◆ antialias() [2/2]

◆ arc()

◆ clip()

◆ color_at() [1/2]

◆ color_at() [2/2]

◆ context()

◆ draw() [1/11]

◆ draw() [2/11]

◆ draw() [3/11]

◆ draw() [4/11]

◆ draw() [5/11]

◆ draw() [6/11]

◆ draw() [7/11]

◆ draw() [8/11]

◆ draw() [9/11]

◆ draw() [10/11]

◆ draw() [11/11]

◆ extents() [1/2]

◆ extents() [2/2]

◆ fill()

◆ fill_preserve()

◆ filter_subordinate()

◆ flood()

◆ high_fidelity()

◆ line()

◆ line_cap() [1/2]

◆ line_cap() [2/2]

◆ line_to()

◆ line_width()

◆ low_fidelity()

◆ mask() [1/2]

◆ mask() [2/2]

◆ move_to()

◆ paint() [1/2]

◆ paint() [2/2]

◆ pop_group()

◆ push_group()

◆ rectangle()

◆ restore()

◆ restore_subordinate_filter()

◆ rotate()

◆ save()

◆ scale()

◆ set() [1/2]

◆ set() [2/2]

◆ set_dash()

◆ set_subordinate_filter()

◆ show_text() [1/2]

◆ show_text() [2/2]

◆ source() [1/4]

◆ source() [2/4]

◆ source() [3/4]

◆ source() [4/4]

◆ stroke()

◆ sync_for_cpu()

◆ target() [1/2]

◆ target() [2/2]

◆ text_size()

◆ translate() [1/2]

◆ translate() [2/2]